Treatment of hydrocarbon oils



Patented Nov. 14, 1933.

STATES PATENT OFFICE TREATMENT or uocmou oms Dakota No Drowlug. Application January 29, 1931 Scrisl No. 5l2,2l 5

l (Dlulm. ((Cl. loo -es) This invention relates to the treotmcntol hy clrccsrhou oils, and refers more particularly to the refining olthe relatively low boiling lu drocarbon dlstllletes.

In one of its soeclilc aspects the invention embodies e. process for the refining of cracked hydrocsrbou olls end comprises subjecting such oils to treatment with sulphur trloxide and steam lo. the presence of u metal.

llhe invention hos-especial application to the refining of the lighter hydrocarbon distilletes in the vapor phase and is perticulurly useful in the reflulhu in the vupor phase of the relatively low Ioolllmg products resulting from the conversion oi hydrocorhou oils by subjecting the sold vopors from the crccklug process during or subsequent to lroctlouotlou to treatment with sulphur trlox ide cud steers lo the presence of o. metal.

The usual method out refining crooked dlstllletes is to subject them to treatment with sulphuric cud slimline solutions, including plumhlte solutions consisting of. llthsrge dissolved in ullre line solutions in vsrlous combinations of treetmeut and subsequently to subject the sold treated product to redlstlllotlou usually in the presence of 'lhe oreseut invention permits the trestmeut oi the hydrocurlcon vapors from the croclslngg process, reducing the cost oi re sc nts and ellmluutluu the redistillotion or re- 3Q cumulus operutlou, olthouuh lt ls within the scope ol the luveutlou to-revsuorlze the product in a. suhssuueut secretion cud sulolect the vapors to Among: the which moy be used sud us er uroles there-oil ore the lollowme: colclum, moeueslum, eluuoluum, zluc, tlu, lrou, cooper, loud, mercury, coholt, ulclrel. chromium, mum

molybdenum, veuodlum, tungsten, sud

the like. It is within the scope of the present luveutlou to employ mixtures of the motels.

applying the process of the invention to practice any suitable equipment may he em= ployed which will permlt the contacting of the hydrocarbon vapors end the sulphur trloxlde and steam with the metals; for example, o suitable.

tower or chamber packed with o selected metol may be employed following the fmctlonstor of u.

cracking system, feeding the sulphur trloxlde cl steam solution tly to the tower countorcurrent to the fiow of the hydrocarbon vapors. thus permitting contact 01' the sulphur trloxlde and steam and hydrocarbons to be treated with the metal. Sulphur trloxlde from" any suitable source,

alone or in combination with steam, my be mtroduced directly into the tower or treating veasel containing the metal. In lieu oil direct peclumg of the tower or treating vessel with the metulllc oxides an inert filling material such as Roschig rings, firebrick, crushed rock, gravel, crushed ceramic material, and the like, suitably coated fi with a, metal, or a. mixture of the some msy be employed. Similarly, any device which permits the efilcient contacting of the vapors undergoing treatment with the metal moy be employed.

The tower or treating vessel containing the 5 metal may be directly connected to o croclzluu unit or to s. rerun or redlstillotlon unit so that the vapors orlslug therefrom may he treoted tn the manner described.

It has been found desirehle to ueutrollze the distillate lmmedlotely utter coudeusotlou elther by passing the coudeusote directly through c body of alkaline such as u solution of ceustlc sods or by woshlng the distillate tree of sulphur trlcxlde end steam with water end/or cllzolles, such es o solution of cuustlc sods, uuxmonlu, or the The neutralizing agent may also he introduced into the vapor line leading to the condenser or lute the condenser itself.

The amount oi sulphur trioxide employed vary from u fraction of e pound to severel loosed on o. horse]. of hydrocurhou cllstlllute treated.

Various temperatures ol treotmeut may he em oloyed'for example, from soc-coo more or s less, and the pressures muy be suh utmosoherlc, utmospheric, or suoerotmospherlc. While the results may vary with the temuerstures employed, the pressures and temperatures are chosen so thst the hydrocarbons are treuted substantially in the vapor chose.

In order to reduce the mteusity of the rouctlou the sulphur trioxide may he admixed with cu inert gas and a. flue gas carbon dioxide and the like, and is preferably introduced at vorlous points in the treating tower.

As specific examples of the. operotlou or the process of invention end of the results oletamed, a. California. crooked distillate of upprom rustely motor fuel boiling range is vaporized cud subjected to treatment with sulphur trloxlde sud em in the presence of zinc. The vapors ere passed at a suitable rate through the tower couto the zinc and approximately one pound per barrel of sulphur trloxide together with steam is introduced into the tower. The untreated product shows a. gum content of approximately 450 mgs. per ccs. and is a reddish brown color. The'sulphur content is-approximately 0.25. The treated product shows a gum content of approx- Elm 'light amber color.

imately 18 mgs. per 100 ccs. and has a color of plus on the Saybolt colorimeter scale. The

sulphur content is reduced to approximately 0.15. The gum determinations are made by the copper dish method.

When the zinc is distributed over pumice stone similar' results to those just described were obtained.

A mixed Mid-Continent and West Texas cracked distillate when treated in the vapor phase with sulphur trioxide and steam employing iron as a contacting agent gives the following results:

The untreated distillate shows a gum content of approximately 350 mgs. per 100 ccs. and a The treated distillate may be reduced in gum content to approximately mgs. per 100 ccs. and a color of approximately 30 on the Saybolt colorimeter scale. The sulphur content may be reduced also.

A California cracked distillate when treated with approximately two pounds of sulphur trioxide in the presence of steam and in the presence of copper shows the following results: The untreated distillate contains approximately 600 mgs. of gum per 100 ccs. The treated distillate may contain approximately 50 mgs. per 100 ccs.

The untreated distillate is a dark reddish amber in color, and the treated distillate may have a color from 25 to 30 on the Saybolt colorimeter scale. The sulphur content is quite appreciably reduced.

With a Mid-Continent distillate containing approximately 350 mgs. of gum per ccs. and having a dark yellow color one may obtain a product containing approximately 25 megs. of gum per 100 ccs. having a color of approximately maawo 25-30 on the Saybolt colorimeter scale and with an appreciable reduction in sulphur content by treatment with sulphur trioxide and steam employing approximately two pounds per barrel, based on the distillate treated and using iron as the contacting agent. Similar results may be obtained by employing sulphur trioxide and steam.

The use of tin gives good results when employed as a contacting agent for the treatment of cracked hydrocarbon vapors with sulphur trioxide and steam. Similar results to those shown for zinc may be obtained, but the results vary in degree.

The above examples are only illustrative and should not be construed as restrictions or limitations on the broad scope of the invention.

The treatment herein described may constitute the sole refining action on the oil, or it may constitute one step in a series of refining steps. It may be preceded by the usual treatments with refining agents such as sulphuric acid, caustid soda, plumbite, filtering earth or the like, and may be succeeded by any combination of the above refining agents, followed, if desired, by

distillation.

We claim as our invention:

A step in the refining treatment of the overhead product of motor fuel boiling range resulting from the cracking of hydrocarbon oil, which comprises subjecting said oil in heated vaporous condition to treatment with sulphur trioxide and steam in the presence of added metal.

JACQUE C. MORRELL. GUSTAV EGLOFF. 

